Nitrosamines Analysis in Pharmaceuticals - Consumables workflow ordering guide

Importance of the topic

Trace nitrosamine impurities in active pharmaceutical ingredients (APIs) and finished drug products are recognized as probable human carcinogens. Even at sub-ppm levels, they pose significant genotoxic and mutagenic risks. Regulatory agencies such as the US FDA, Health Canada and the European Pharmacopoeia have issued guidance requiring sensitive, reliable analytical workflows to detect and quantify these compounds and ensure patient safety.

Objectives and overview

This application guide presents three FDA-recommended gas chromatographic mass spectrometry (GC/MS) methods for screening and quantitating nitrosamines in pharmaceuticals. Method 1 and Method 2 employ headspace injection with a single quadrupole GC/MS (GC/SQ-MS) to detect up to four nitrosamines. Method 3 uses liquid injection with a triple quadrupole GC/MS (GC/TQ-MS/MS) to simultaneously quantify five nitrosamines with enhanced sensitivity and specificity. A consumables ordering guide is included to streamline method implementation.

Methodology and used instrumentation

• Method 1 (GC/SQ-MS headspace): Detection of NDMA and NDEA by SIM. Recommended setup: Agilent 8890 GC with 7697A headspace sampler and 5977B MSD. LODs: 0.005 ppm (NDMA), 0.02 ppm (NDEA).
• Method 2 (GC/SQ-MS headspace): Expanded SIM assay for NDMA, NDEA, NEIPA and NDIPA. Platform: Agilent 7890B GC, 7697A HS sampler and 5977A MSD. Achieved LODs ~0.01 ppm for drug substances and products.
• Method 3 (GC/TQ-MS/MS liquid injection): MRM quantitation of five nitrosamines (NDMA, NDEA, NEIPA, NDIPA, NDBA). Instrument: Agilent 7890B or 8890 GC coupled to 7010B triple quadrupole MS. Enhanced LOQs down to 0.005–0.025 ppm in API and 0.002–0.040 ppm in finished dosage forms.

Main results and discussion

All three methods meet or exceed FDA guidance sensitivity. Headspace-based GC/SQ methods offer fast screening of two to four analytes with LODs in the 0.01–0.02 ppm range. The GC/TQ approach delivers superior specificity and sub-ppb quantitation for five analytes, reducing potential interferences and improving confidence in trace-level measurements. Representative chromatograms demonstrate clear separation and stable retention times for each nitrosamine.

Benefits and practical applications

• Regulatory compliance: Meets US FDA, EDQM and Health Canada guidelines.
• Workflow efficiency: Preconfigured methods for headspace and liquid injections.
• Consumable selection: Comprehensive list of columns, liners, vials and standards to simplify ordering.
• Analytical flexibility: Choice of single or triple quadrupole detection based on sensitivity requirements.

Future trends and opportunities

Advances in high-efficiency ion sources and ultra-inert flow paths will further lower LOQs and improve robustness. Integrated headspace/liquid injection in a single inlet enables rapid method switching. Emerging LC-MS/MS and LC-Q-TOF techniques may complement GC-based assays, expanding the analytical toolkit for nitrosamine and other mutagenic impurity testing. Automation and data-management software will streamline routine compliance workflows.

Conclusion

The three FDA-recommended GC/MS methods provide a tiered analytical strategy for detecting and quantifying nitrosamines in APIs and drug products. Laboratories can select headspace GC/SQ methods for rapid screening or liquid injection GC/TQ for ultra-sensitive quantitation. The accompanying consumables guide ensures consistent, high-quality results and regulatory compliance.

Reference

1. Barreras A., Gurk-Turner C. Angiotensin II Receptor Blockers. Proc (Bayl Univ Med Cent), 2003, 16(1):123–126.
2. Nitrosamine Analysis in Pharmaceuticals using GC/TQ and LC/TOF consumables workflow guide, Agilent 5994-2977EN.
3. Combined NDMA and NDEA Impurity Assay by GC/MS-Headspace, US FDA 2019.
4. Analysis of NDMA and NDEA Using Agilent 7697A HS Sampler, 8890/5977 GC/MSD, Agilent 5994-1132EN.
5. Combined HS NDMA, NDEA, NEIPA and NDIPA Assay by GC-MS/MS, US FDA 2019.
6. Combined Direct Injection NDMA, NDEA, NEIPA, NDIPA, NDBA Assay by GC-MS/MS, US FDA 2019.
7. Nitrosamine Impurities Application Guide, Agilent 5994-2393EN.
8. Quantification of Nitrosamine Impurities in Metformin Using GC/MS/MS, Agilent 5994-2419EN.
9. Analysis of Five Nitrosamine Impurities Using GC/MS/MS, Agilent 5994-1821EN.